Access Levels - Administrator
Administrator-level access gives you full access to all areas of the site within the relevant group, irrespective of any other permissions that has been set for that person in the group.
Administrator access to a top-level group (eg. one which has no parent) also gives the ability to manage event types, as well as types of people, together with management of other groups in the system.
As a group administrator, you can also add sub-groups within your group.